From 9cb218131de1c59dca9063b2efe876f053f316af Mon Sep 17 00:00:00 2001 From: Michael Holzheu Date: Wed, 11 Sep 2013 14:24:51 -0700 Subject: vmcore: introduce remap_oldmem_pfn_range() For zfcpdump we can't map the HSA storage because it is only available via a read interface. Therefore, for the new vmcore mmap feature we have introduce a new mechanism to create mappings on demand. This patch introduces a new architecture function remap_oldmem_pfn_range() that should be used to create mappings with remap_pfn_range() for oldmem areas that can be directly mapped. For zfcpdump this is everything besides of the HSA memory. For the areas that are not mapped by remap_oldmem_pfn_range() a generic vmcore a new generic vmcore fault handler mmap_vmcore_fault() is called. This handler works as follows: * Get already available or new page from page cache (find_or_create_page) * Check if /proc/vmcore page is filled with data (PageUptodate) * If yes: Return that page * If no: Fill page using __vmcore_read(), set PageUptodate, and return page Signed-off-by: Michael Holzheu Acked-by: Vivek Goyal Cc: HATAYAMA Daisuke Cc: Jan Willeke Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/crash_dump.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/linux/crash_dump.h b/include/linux/crash_dump.h index 6571f828e313..fe68a5a98583 100644 --- a/include/linux/crash_dump.h +++ b/include/linux/crash_dump.h @@ -17,6 +17,9 @@ extern int __weak elfcorehdr_alloc(unsigned long long *addr, extern void __weak elfcorehdr_free(unsigned long long addr); extern ssize_t __weak elfcorehdr_read(char *buf, size_t count, u64 *ppos); extern ssize_t __weak elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos); +extern int __weak remap_oldmem_pfn_range(struct vm_area_struct *vma, + unsigned long from, unsigned long pfn, + unsigned long size, pgprot_t prot); extern ssize_t copy_oldmem_page(unsigned long, char *, size_t, unsigned long, int); -- cgit v1.2.3